[PATCH] D34904: [CGP] use subtract of cmps for result of memcmp expansion

Eli Friedman via Phabricator via llvm-commits llvm-commits at lists.llvm.org
Thu Jul 6 17:22:32 PDT 2017


efriedma added inline comments.


================
Comment at: test/CodeGen/X86/memcmp.ll:38
+; X64-NEXT:    seta %al
+; X64-NEXT:    sbbl $0, %eax
 ; X64-NEXT:    retq
----------------
Potential alternative sequence: instead of xorl+cmpw+seta+sbbl, just generate a "subl", like we do for length 1.


https://reviews.llvm.org/D34904





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